ci: disable background tasks in review job

(cherry picked from commit da79eca3c0)

.github/workflows/claude-review.yml

@@ -71,6 +71,8 @@ jobs:
         run: echo "base=$(gh pr view ${{ github.event.issue.number }} --json baseRefName --jq .baseRefName)" >> "$GITHUB_OUTPUT"
 
       - uses: anthropics/claude-code-action@9ca9355b36297178e28d37c799d1c9c8a28e6507
+        env:
+          CLAUDE_CODE_DISABLE_BACKGROUND_TASKS: "1"
         id: claude
         with:
           claude_code_oauth_token: ${{ secrets.CLAUDE_CODE_OAUTH_TOKEN }}